The objectives of this project are: (1) the investigation of structure-activity techniques as applied to antitumor data; (2) quantitative correlations of screening data with structural features among antitumor agent congeners; (3) quantitative and qualitative correlations between structure and antitumor activity among large numbers of structurally unrelated compounds; (4) the use of the correlations obtained to: (a) generate leads for new synthesis, (b) increase the rationale for selection of new compounds to be tested and (c) reduce the number of synthetic analogs necessary to obtain the optimally active member of a new series. Antitumor agent families under active study by the Hansch technique are adriamycin, terphthalanilide, Muracil D and 5-fluorouracil.